Stop mechanism.



No. 638,!82. Patented Nov. 28, |899.

F. T. LE|L|cH. STOP MECHANISM.

(Application led'Mr. 11, 1899.)

(No Model.)

Nonms nung um. Eno'ruumo Uurrnn Srl-iras Farnivr Ormea.

FRANCIS T. LEILICI-I, OF SAN FRANCISCO, CALIFORNIA, ASSIGNOR OF ONE- HALF TO JAMES G. SIMONTON, OF SAME PLACE.

STOP MECHANISM.

SPECIFICATION forming part of Letters Patent No. 638,182, dated November 28, 1899.

Original application tiled February 17, 1898, Serial No. 670,679. Divided and this application filed March 11,1899. Serial N0. 708,714-1 (No model i To all whom it may concern:

Be it known that I, FRANCIS T. LniLrcn, a citizen of the United States, residing at San Francisco, in the county of San Francisco and State of California, have invented certain new and useful Improvements in Stop Mechanisms; and I do hereby declare the following to be a full, clear, and exact description of said invention, such as will enable others lo skilled in the art to which it most nearly appertains to make, use, and practice the same.

My invention relates to improvements in stop mechanisms for machinery, my object being toprovide a structure by which the moving parts are stopped quickly, but without shook.

To this end and also to im rove genera-ll i' vention consists in the various matters here- 2o inafter described and claimed.

The present device (although in no wise limited to such use) 4is particularly applicable to sewingmachines and in the accompanying drawings is illustrated as so applied.

z5 In the drawings, Figure lis a top plan view of a portion of a sewing-machine with my present invention applied, and Fig. 2 isa side elevation of the same.

Passing now to a detail description, the

3o driving mechanism is providedl with the fixed and loose pulleys A A2, and over the pulleys is carried the driving-belt A3,which is controlled by the shifting yoke A1. The yoke A4 is extended from the brake-slice A5. The

brake-shoe A5 is adapted to it over the hub of the xed pulley and rear extension of the driving-shaft and is provided with a frictionsurface A1", abutting the face of the fixed pulley. This friction-surface in the present 4o construction is formed of leather. Any other non-metallic material better adapted to the purpose could be used without altering the spirit of the invention. The object of the friction-surface is to strike upon the pulley and by the friction partly arrest the pulley and the driving-shaft upon which it is fixed before it is engaged by the pin A1.

The brake-shoe is provided with the guiderod A8,which is set in an extension A9, set out 5o from the head of the machine. The extension is provided with an elongated slot A10,

through which is extended the pin A11 set out from the side of theguide-rod AS. Engaging the pin A11 by means of a yoke A12 is the bellcrank A13. This bell-crank A1*3 is pivotally 55 mounted upon the frame of the machine at A11. It is provided with a long arm A13', to which is attached one end of the spiral spring A15, while the free end of said long arm is adapted to be connected to a suitable mech- 6o anism for depressing it. The upper end of the spring A15 is attached to a hook A15,which is extended through a perpendicular perforation in the bracket A1. The hook A11 isprovided with a threaded shank or body which is engaged by the set-nut A11. It is by means of the set-nut A1T and the threaded shank of the hook A16 that the tension of the spring A15 is varied. By means of this arrangement the normal position of the stopping mechanism 7o is that the spring A15 raises the long arm of the lever A13 and throws the yoke-arm of the same, carrying the pin A11 and the rod A10, forward, and the latter being rigidly attached to the brake-shoe sets the surface A6 against 75 the surface of the pulley A with a pressure dependent upon the strength of thespring A15.

As before stated, the shifting yoke coni trolling the belt A3 is attached to the brakeshoe, and as the shoe is drawn against the 8o fixed pulley A the belt is moved from it to the loose pulley A2.

While the brake-shoe would eventually stop the operation of the mechanism, it would not do so accurately enough to serve its purpose in certain classes of machines, as in sewingmachines. It is to arrest the action of the driving mechanism definitively at a certain point that I have provided the pin A1, which is heldin the end of the arm A15, pivotally 9o mounted on the frame of the brake-shoe. The pin is extended through the perforation provided for it in the brake-shoe A5. The socket A19 is formed in the fixed pulley A', in which it is designed the pin A7 will fall. To make 95 the entrance of the pin striking the socket more certain, the same is provided with an inclined surface formed in the face of the pulley A', leading into the socket. The arm A18 is held against the back of the shoe A5 by means of a spring A20. In its operation the IOO shoe A5 is set against the pulley A', and the end of the pin A7 strikes upon the surface of the pulley in advance of the socket A19 and in the path of the same. The friction-surface A6 of the brake considerably retards the motion of the pulley and driving-shaft before the socket A19 advances to the pin A7. In doing so the pin runs down the incline and when opposite the socket enters the same by reason of the pressure put upon the arm by the spiral spring A20, said pin thus engaging the shoulder A21. Thus is the driving mechanism rapidly and accurately arrested in an ascertained and desired position. By reason of the arrangement, however, by which the driving mechanism is partially and gradually arrested by a friction-brake before being finally stopped by the positive and rigid engaging member I have avoided unnecessary shocks or jars to the driving mechanism.

In certain classes of machines (as in button-sewing machines) it is desirable to cause the stop mechanism to act automatically and at predetermined intervals, and a machine of this type is here illustrated. Upon a disk X, suitably geared to the driving-shaft, is a pin E6. The office of said pin is to trip a trigger E5, interposed between the controlling mechanism--fil e., the disk and its pin-and the stopping mechanism. The trigger E5 is pivotally mounted upon the frame of the machine and is provided, as shown, with two arms extending upon each side of the pivotal center. One arm rests within the path of the pin E6 upon the disk and is moved by said pin when the disk is rotated. The other arm carries a pin E7, which rests in the path of the end of the rod A8 of the stopping mechanism, said pin being normally held in this position against a suitable stop .fr by means of the spring ES. Normally the parts are, as illustrated, with the stop mechanism, held out of operative position. WVhen, however, the disk X, through its pin EG, trips the trigger E5, the stop mechanism acts and the machine is thr'own out of action, to remain so until the operator depresses the long arm A13' of the bell-crank lever A13, thus positively throwing the stop mechanism into inoperative position and permitting the trigger E5 to return to normal position, and thus hold the stop mechanism out of action.

My present application is a division of my pending application filed February 17, 1898, Serial No. 670,679.

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent, is-

l. The combination in a mechanism of the nature indicated of a driving mechanism having a fixed driving-pulley provided with a shoulder; a stopping mechanism having a non-metallic friction-faced shoe adapted to be set against the said pulley; a movable arm to engage the said shoulder subsequent to the setting of the said shoe to definitively arrest the said pulley and driving mechanism; a spring adapted to set the said shoe and arm against the said pulley; a device to hold the said shoe and arm awayT from the said pulley during the operation of the driving mechanism; and suitable connections between the said driving mechanism and said device to release the latter automatically to permit the said spring to set the said shoe and arm, substanti'ally as described.

2. The combination in a mechanism of the nature indicated of a driving mechanism having a fixed pulley, the face of said pulleybeing provided with a shoulder; a brake-shoe havinga non-metallic `face mounted in guides perpendicular to the face of the driving-pulley and adapted to be set against the said pulley; a stopping-arm to engage the said shoulder subsequent to the setting of the said shoe to definitively arrest the said pulley; a spring adapted to move the said shoe and arm against the said pulley; a device to prevent the said spring from setting the said shoe and stop-arm; and suitable connecting mechanism between the driving mechanism and the said device to release the latter automatically at a predetermined time in the operation of the driving mechanism to permit the spring to set the shoe and arm, substantially as described.

3. The combination in a mechanism of the rnature indicated of a driving mechanism having a fixed driving-pulley provided with a recess formed in its face; a brake-shoe with a non-metallic friction-face adapted to be set against the said pulley and mounted in guides perpendicular to the face of the driving-pulley; a spring-actuated arm mounted upon the said shoe and adapted to strike on the face of the said pulley with the said shoe to engage the said recess subsequent to the setting of the said shoe; a guide-rod connected to the said shoe and mounted in the said guides and extending into the path of a setting device; a spring adapted to draw the said shoe and guide-rod toward the said setting device and said pulley; and a connecting mechanism between the said setting device and the driving mechanism to release the said guide-rod at a predetermined time in the operation of the driving mechanism, substantially as described.

In testimony whereof I have hereunto set my hand this 2d day of March, 1899.

FRANCIS T. LEILICH.

Witnesses:

E. F. MuRDocK, BALDWIN VALE.

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